1. Field of the Invention
The present invention relates of a method for stabilizing a flame retarded polyurethane foam against scorching and the product thereof.
2. Description of the Prior Art
In copending U.S. Application Ser. No. 682,520, filed on Dec. 17, 1984, of Barry A. Jacobs, entitled "Method of Preventing Scorch in a Polyurethane Foam and Product Thereof", it was proposed to use an N-alkanoyl-N,N'-dialkylphenylenediamine compound as a scorch inhibitor in a flame retarded polyurethane foam formulation. The compounds of this type were effective in curing the thermal scorch which occurred due, most likely, to the degradation of the halogen-phosphorus flame retardants customarily used in such foams.
A second type of discoloration, which is deemed to be a chemical scorch, can be ameliorated by a combined use of one or more of the aforementioned substituted N,N'-dialkylphenylenediamine compounds and a fluorescent (or "optical") brightener.